SURROUND SOUND FORMAT HISTORY-DOLBY

DOLBY SOUND 

Ray Dolby, Founder and Director Emeritus of Dolby Laboratories, Inc

DOLBY NR ANALOG

-1971 A Clockwork Orange- 1st Movie that used Dolby A NR

ON THE MAGNETIC Soundtrack of 35mm

1986

DOLBY SR (Spectral Recording) to reduce the noise

4 CHANNELS LCRS

The process was built into to he reader at the cinema

Attached to the projector

4:2:4 Matrix SYSTEM

THE AGE OF DOLBY

1975 Dolby stereo

A START WAS BORN 1ST MOVIE- get the credit

Dolby labs introduced a new sound technology for 35 mm print called Dolby Stereo

Star Wars

LCRS-.2 

.2 - 2 X SUB WOOFERS

FORMATS

1. Betta

Late 70's

2 VHS

Phillips developed it...

 1st Commercially available video recorder was introduced 1978 Model 1500

Dolby Surround 

Home Theatre

4 Channel MA

TROX

ANY 2 TRACKS COULD BE DECODED INTO SURROUND SOUNDS

Dolby Pro Logic IIx

1st and only technology to expand any any 5.1 or 6.1 7.1 

Dolby SR (ANALOG)

DOLBY SR-D Digital

Introduced 1992

 A Digital Optical Soundtrack Located between the sprocket holes on the side of the

35 mm released print 

0 and 1  Digital

5.1 Channels

L C R Ls R s

LFE - Only  used for bass frequencies only used for more impact - explosion

FX CHANNEL

0.1  Bandwith Limited 

Low Frequency CTs 

(20 -200 kHz

3 LASER DISC 

LCRS

Format AC-3 Audio Code

 Notes

AC3Filter is high quality freeware DirectShow audio decoder and processor filter used to decode audio tracks in movies (MPEG4 and DVD others). It has a priority on wide functionality and convenient settings.

Lulu's notes

I have never seen the Ac-3 Audio code but I would like to see how it works in real life.
The rest is pretty straight forward.